Restund is a modular and flexible STUN and TURN Server, with IPv4 and IPv6
support. Supported IETF RFCs:

* RFC 5389 - Session Traversal Utilities for NAT (STUN)
* RFC 5766 - Traversal Using Relays around NAT (TURN): Relay Extensions to
             Session Traversal Utilities for NAT (STUN)
* RFC 5780 - NAT Behavior Discovery Using Session Traversal Utilities for
             NAT (STUN)
* RFC 6156 - Traversal Using Relays around NAT (TURN) Extension for IPv6
